Now it's clear, it is for a job in a Court!
In addition to what they advised, add these also:
1. Carry your originals with two sets of Xerox copies and recent passport-size photos, one or two sheets of fresh paper, a pen, and a pencil.
2. Either don't carry a mobile phone or, if carried, ensure it's switched off.
3. Wear neat, clean clothes, buttoned up, polished chappals or shoes. Sit erect, don't rest your arms on the desk, and be attentive to what they are talking to you.
4. When directed to enter, if the door is closed, tap the door gently, open it, and ask for their permission to enter. After entering, calmly and quietly walk up to the seat and stand until you are asked to sit.
5. Don't ever panic. Reply only when asked; otherwise, clearly understand what they are addressing you. If you don't fully understand the question put forth before you expecting an answer, ask them to repeat with, "Excuse me, if you don't mind, could you repeat the question?" If the question asked is in English, reply also in English; if it is in vernacular, reply also in the same language. By chance, if you don't know either of these languages, apologize for the same and seek their permission to answer in whatever language you are comfortable with.
6. If possible, rehearse with your friends who have interview experience.
7. Be genuine and truthful. Answer briefly, and when you have no answer, say frankly, "Sorry sirs, I don't know the answer." Don't ever try to bluff or mislead them.
8. When finished, stand up quietly, say "Thank you very much," looking at all those in the panel, and walk back without a murmur.
If possible, get some knowledge of what type of tasks you have to do if appointed, and prepare well on GK, judicial systems in the country, etc.
All the best to both of you.